These images are composites of separate exposures acquired by the ACS and the WFC3 instruments on the Hubble Space Telescope. Several filters were used to sample broad and narrow wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are:

Westerlund 2 is surrounded by the star-forming region Gum 29. The heaviest cluster stars are unleashing a torrent of ultraviolet radiation and hurricane-force winds streaming with charged particles, etching away the enveloping hydrogen gas cloud from where the cluster formed. The nebula reveals a fantasy landscape of pillars, ridges, valleys, and reddish-brown filaments of dense gas and dust. The brightest stars in the image are Milky Way foreground stars not associated with Westerlund 2.